nautilus property page API change

[Dave Camp <dave ximian com>]

This is a quick heads up for people implementing bonobo property pages
in nautilus.

In order to support multi-file property dialogs, some changes have been
made to the api:

1) Components can specify the nautilus:can_handle_multiple_files
attribute for property pages.

<oaf_attribute name="nautilus:can_handle_multiple_files" type="boolean"
value="true"/>

2) A new property, 'uris', of type sequence<string>, has been added, and
'URI' has been deprecated.  Components should switch to 'uris' once 2.4
has been released.  'URI' will still be supported, but will start
spewing a g_warning when 2.4 is released.

have fun,
-dave